What is the purpose of backflow prevention?

The primary purpose of backflow prevention is to ensure that contaminated water does not re-enter the clean water supply. Backflow can occur when there is a change in pressure in the water system, causing water to flow in the reverse direction. This can happen due to various reasons, such as bursts in water mains or high demand times that create a vacuum. To mitigate this risk, backflow prevention devices are installed to maintain the integrity of the potable water supply, ensuring that any potential contaminants are contained and do not affect the cleanliness of the drinking water.

When examining the other options, increasing water pressure is not a function of backflow prevention; rather, it is managed through the water distribution system’s design and pumps. Draining pipes during maintenance is a necessary operational procedure but is unrelated to the primary intent of preventing contamination. Enhancing water taste by adding minerals does not relate to backflow prevention and focuses instead on treatment processes meant to improve the quality of the water provided. Hence, the correct choice directly addresses the critical public health need to maintain a clean and safe drinking water supply.